Epizooic diatoms on the cerci of Ephemeroptera (Caenidae) Naiads

Abstract

Using scanning electron microscopy, epizooic diatoms were observed growing on the cerci of Caenis amica Hagen naiads (Ephemeroptera, Caenidae). Meridion circulare (Greville) C. Agardh was the most abundant, followed by Synedra rumpens Kützing, then Cocconeis pediculus Ehrenberg. Other diatom species observed from substrates in Cedar Creek, Isabella County, Michigan were not observed on the cerci. No diatoms were observed on Ephemerellidae naiads.